ntmisc.c

Netscape NSPR库源码

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/MPL/
 * 
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 * 
 * The Original Code is the Netscape Portable Runtime (NSPR).
 * 
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are 
 * Copyright (C) 1998-2000 Netscape Communications Corporation.  All
 * Rights Reserved.
 * 
 * Contributor(s):
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL"), in which case the provisions of the GPL are applicable 
 * instead of those above.  If you wish to allow use of your 
 * version of this file only under the terms of the GPL and not to
 * allow others to use your version of this file under the MPL,
 * indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by
 * the GPL.  If you do not delete the provisions above, a recipient
 * may use your version of this file under either the MPL or the
 * GPL.
 */

/*
 * ntmisc.c
 *
 */

#include "primpl.h"

char *_PR_MD_GET_ENV(const char *name)
{
    return getenv(name);
}

/*
** _PR_MD_PUT_ENV() -- add or change environment variable
**
**
*/
PRIntn _PR_MD_PUT_ENV(const char *name)
{
    return(putenv(name));
}


/*
 **************************************************************************
 **************************************************************************
 **
 **     Date and time routines
 **
 **************************************************************************
 **************************************************************************
 */

#include <sys/timeb.h>

/*
 *-----------------------------------------------------------------------
 *
 * PR_Now --
 *
 *     Returns the current time in microseconds since the epoch.
 *     The epoch is midnight January 1, 1970 GMT.
 *     The implementation is machine dependent.  This is the
 *     implementation for Windows.
 *     Cf. time_t time(time_t *tp)
 *
 *-----------------------------------------------------------------------
 */

PR_IMPLEMENT(PRTime)
PR_Now(void)
{
    PRInt64 s, ms, ms2us, s2us;
    struct timeb b;

    ftime(&b);
    LL_I2L(ms2us, PR_USEC_PER_MSEC);
    LL_I2L(s2us, PR_USEC_PER_SEC);
    LL_I2L(s, b.time);
    LL_I2L(ms, b.millitm);
    LL_MUL(ms, ms, ms2us);
    LL_MUL(s, s, s2us);
    LL_ADD(s, s, ms);
    return s;       
}

/*
 * The following code works around a bug in NT (Netscape Bugsplat
 * Defect ID 47942).
 *
 * In Windows NT 3.51 and 4.0, if the local time zone does not practice
 * daylight savings time, e.g., Arizona, Taiwan, and Japan, the global
 * variables that _ftime() and localtime() depend on have the wrong
 * default values:
 *     _tzname[0]  "PST"
 *     _tzname[1]  "PDT"
 *     _daylight   1
 *     _timezone   28800
 *
 * So at startup time, we need to invoke _PR_Win32InitTimeZone(), which
 * on NT sets these global variables to the correct values (obtained by
 * calling GetTimeZoneInformation().
 */

#include <time.h>     /* for _tzname, _daylight, _timezone */

void
_PR_Win32InitTimeZone(void)
{
    OSVERSIONINFO version;
    TIME_ZONE_INFORMATION tzinfo;

    version.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
    if (GetVersionEx(&version) != FALSE) {
        /* Only Windows NT needs this hack */
        if (version.dwPlatformId != VER_PLATFORM_WIN32_NT) {
            return;
        }
    }

    if (GetTimeZoneInformation(&tzinfo) == 0xffffffff) {
        return;  /* not much we can do if this failed */
    }
 
    /* 
     * I feel nervous about modifying these globals.  I hope that no
     * other thread is reading or modifying these globals simultaneously
     * during nspr initialization.
     *
     * I am assuming that _tzname[0] and _tzname[1] point to static buffers
     * and that the buffers are at least 32 byte long.  My experiments show
     * this is true, but of course this is undocumented.  --wtc
     *
     * Convert time zone names from WCHAR to CHAR and copy them to
     * the static buffers pointed to by _tzname[0] and _tzname[1].
     * Ignore conversion errors, because it is _timezone and _daylight
     * that _ftime() and localtime() really depend on.
     */

    WideCharToMultiByte(CP_ACP, 0, tzinfo.StandardName, -1, _tzname[0],
            32, NULL, NULL);
    WideCharToMultiByte(CP_ACP, 0, tzinfo.DaylightName, -1, _tzname[1],
            32, NULL, NULL);

    /* _timezone is in seconds.  tzinfo.Bias is in minutes. */

    _timezone = tzinfo.Bias * 60;
    _daylight = tzinfo.DaylightBias ? 1 : 0;
    return;
}

/*
 ***********************************************************************
 ***********************************************************************
 *
 * Process creation routines
 *
 ***********************************************************************
 ***********************************************************************
 */

/*
 * Assemble the command line by concatenating the argv array.
 * On success, this function returns 0 and the resulting command
 * line is returned in *cmdLine.  On failure, it returns -1.
 */
static int assembleCmdLine(char *const *argv, char **cmdLine)
{
    char *const *arg;
    char *p, *q;
    int cmdLineSize;
    int numBackslashes;
    int i;
    int argNeedQuotes;

    /*
     * Find out how large the command line buffer should be.
     */
    cmdLineSize = 0;
    for (arg = argv; *arg; arg++) {
        /*
         * \ and " need to be escaped by a \.  In the worst case,
         * every character is a \ or ", so the string of length
         * may double.  If we quote an argument, that needs two ".
         * Finally, we need a space between arguments, and
         * a null byte at the end of command line.
         */
        cmdLineSize += 2 * strlen(*arg)  /* \ and " need to be escaped */
                + 2                      /* we quote every argument */
                + 1;                     /* space in between, or final null */
    }
    p = *cmdLine = PR_MALLOC(cmdLineSize);
    if (p == NULL) {
        return -1;
    }

    for (arg = argv; *arg; arg++) {
        /* Add a space to separates the arguments */
        if (arg != argv) {
            *p++ = ' '; 
        }
        q = *arg;
        numBackslashes = 0;
        argNeedQuotes = 0;

        /* If the argument contains white space, it needs to be quoted. */
        if (strpbrk(*arg, " \f\n\r\t\v")) {
            argNeedQuotes = 1;
        }

        if (argNeedQuotes) {
            *p++ = '"';
        }
        while (*q) {
            if (*q == '\\') {
                numBackslashes++;
                q++;
            } else if (*q == '"') {
                if (numBackslashes) {
                    /*
                     * Double the backslashes since they are followed
                     * by a quote
                     */
                    for (i = 0; i < 2 * numBackslashes; i++) {
                        *p++ = '\\';
                    }
                    numBackslashes = 0;
                }
                /* To escape the quote */
                *p++ = '\\';
                *p++ = *q++;
            } else {
                if (numBackslashes) {
                    /*
                     * Backslashes are not followed by a quote, so
                     * don't need to double the backslashes.
                     */
                    for (i = 0; i < numBackslashes; i++) {
                        *p++ = '\\';
                    }
                    numBackslashes = 0;
                }
                *p++ = *q++;
            }
        }

        /* Now we are at the end of this argument */
        if (numBackslashes) {
            /*
             * Double the backslashes if we have a quote string
             * delimiter at the end.
             */
            if (argNeedQuotes) {
                numBackslashes *= 2;
            }
            for (i = 0; i < numBackslashes; i++) {
                *p++ = '\\';
            }
        }
        if (argNeedQuotes) {
            *p++ = '"';
        }
    } 

    *p = '\0';
    return 0;
}

/*
 * Assemble the environment block by concatenating the envp array
 * (preserving the terminating null byte in each array element)
 * and adding a null byte at the end.
 *
 * Returns 0 on success.  The resulting environment block is returned
 * in *envBlock.  Note that if envp is NULL, a NULL pointer is returned
 * in *envBlock.  Returns -1 on failure.
 */
static int assembleEnvBlock(char **envp, char **envBlock)
{
    char *p;
    char *q;
    char **env;
    char *curEnv;
    char *cwdStart, *cwdEnd;
    int envBlockSize;

    if (envp == NULL) {
        *envBlock = NULL;
        return 0;
    }

    curEnv = GetEnvironmentStrings();

    cwdStart = curEnv;
    while (*cwdStart) {
        if (cwdStart[0] == '=' && cwdStart[1] != '\0'
                && cwdStart[2] == ':' && cwdStart[3] == '=') {
            break;
        }
        cwdStart += strlen(cwdStart) + 1;
    }
    cwdEnd = cwdStart;
    if (*cwdEnd) {
        cwdEnd += strlen(cwdEnd) + 1;
        while (*cwdEnd) {
            if (cwdEnd[0] != '=' || cwdEnd[1] == '\0'
                    || cwdEnd[2] != ':' || cwdEnd[3] != '=') {
                break;
            }
            cwdEnd += strlen(cwdEnd) + 1;
        }
    }
    envBlockSize = cwdEnd - cwdStart;

    for (env = envp; *env; env++) {
        envBlockSize += strlen(*env) + 1;
    }
    envBlockSize++;

    p = *envBlock = PR_MALLOC(envBlockSize);
    if (p == NULL) {
        FreeEnvironmentStrings(curEnv);
        return -1;
    }

    q = cwdStart;
    while (q < cwdEnd) {
        *p++ = *q++;
    }
    FreeEnvironmentStrings(curEnv);

    for (env = envp; *env; env++) {
        q = *env;
        while (*q) {
            *p++ = *q++;
        }
        *p++ = '\0';
    }
    *p = '\0';
    return 0;
}

/*
 * For qsort.  We sort (case-insensitive) the environment strings
 * before generating the environment block.
 */
static int compare(const void *arg1, const void *arg2)
{
    return _stricmp(* (char**)arg1, * (char**)arg2);
}

PRProcess * _PR_CreateWindowsProcess(
    const char *path,
    char *const *argv,
    char *const *envp,
    const PRProcessAttr *attr)
{
    STARTUPINFO startupInfo;
    PROCESS_INFORMATION procInfo;
    BOOL retVal;
    char *cmdLine = NULL;
    char *envBlock = NULL;
    char **newEnvp = NULL;
    const char *cwd = NULL; /* current working directory */
    PRProcess *proc = NULL;

    proc = PR_NEW(PRProcess);
    if (!proc) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        goto errorExit;
    }

    if (assembleCmdLine(argv, &cmdLine) == -1) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        goto errorExit;
    }

    /*
     * If attr->fdInheritBuffer is not NULL, we need to insert
     * it into the envp array, so envp cannot be NULL.
     */
    if ((envp == NULL) && attr && attr->fdInheritBuffer) {
        envp = environ;
    }

    if (envp != NULL) {
        int idx;
        int numEnv;
        int newEnvpSize;

        numEnv = 0;
        while (envp[numEnv]) {
            numEnv++;
        }
        newEnvpSize = numEnv + 1;  /* terminating null pointer */
        if (attr && attr->fdInheritBuffer) {
            newEnvpSize++;
        }
        newEnvp = (char **) PR_MALLOC(newEnvpSize * sizeof(char *));
        for (idx = 0; idx < numEnv; idx++) {
            newEnvp[idx] = envp[idx];
        }
        if (attr && attr->fdInheritBuffer) {
            newEnvp[idx++] = attr->fdInheritBuffer;
        }
        newEnvp[idx] = NULL;
        qsort((void *) newEnvp, (size_t) (newEnvpSize - 1),
                sizeof(char *), compare);
    }
    if (assembleEnvBlock(newEnvp, &envBlock) == -1) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        goto errorExit;
    }

    ZeroMemory(&startupInfo, sizeof(startupInfo));
    startupInfo.cb = sizeof(startupInfo);

    if (attr) {
        PRBool redirected = PR_FALSE;

        /*
         * XXX the default value for stdin, stdout, and stderr
         * should probably be the console input and output, not
         * those of the parent process.
         */
        startupInfo.hStdInput = GetStdHandle(STD_INPUT_HANDLE);
        startupInfo.hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);
        startupInfo.hStdError = GetStdHandle(STD_ERROR_HANDLE);
        if (attr->stdinFd) {
            startupInfo.hStdInput = (HANDLE) attr->stdinFd->secret->md.osfd;
            redirected = PR_TRUE;
        }
        if (attr->stdoutFd) {
            startupInfo.hStdOutput = (HANDLE) attr->stdoutFd->secret->md.osfd;
            redirected = PR_TRUE;
        }
        if (attr->stderrFd) {
            startupInfo.hStdError = (HANDLE) attr->stderrFd->secret->md.osfd;
            redirected = PR_TRUE;
        }
        if (redirected) {
            startupInfo.dwFlags |= STARTF_USESTDHANDLES;
        }
        cwd = attr->currentDirectory;
    }

    retVal = CreateProcess(NULL,
                           cmdLine,
                           NULL,  /* security attributes for the new
                                   * process */
                           NULL,  /* security attributes for the primary
                                   * thread in the new process */
                           TRUE,  /* inherit handles */